The present invention relates to the field of systems for the control of termites and other pests that access building structures from underground. More particularly, the present invention relates to the field of distribution structures and methods of using the structures to control termites and other pests that access a building structure from underground.
Prior to the 1988 ban on the use of chlordane for termite protection, a single treatment of a building site prior to construction provided long-term protection against termites. The practice at that time entailed a single application to the soil prior to the pouring of foundations and cement slabs. Tests conducted as long as 52 years after such treatment indicated no signs of breakdown.
However, because of environmental problems associated with chlordane, other chemicals have had to be substituted. The chemicals in use today for termite control are considerable more expensive. Further, their effective life has not been reliably tested. Typically, the industry guarantees the life of such products applied as a pre-treat for only five years.
At the end of five years, the homeowner must decide whether to gamble and risk a termite invasion or to apply a re-treatment. When possible, the re-treatment consists of drilling holes no less than every two feet around the perimeter of the home and also adjacent to plumbing protrusions. The chemical is then injected, typically at the rate of four gallons per ten lineal feet. Frequently, the process becomes even more difficult and expensive. If the homeowner has planted trees or shrubs or has installed sidewalks or pools that interfere, it becomes necessary to apply treatment from inside the structure. This entails, in many cases, pulling up carpets, drilling holes through ceramic tiles and cement slabs and then applying the chemicals through the holes. After all this, and at a cost more than twice that of the original pre-treat, the re-treatment is typically only guaranteed one more year.
Accordingly, inventions involving structures and methods directed at a solution for preventative termite re-treatment have been heretofore disclosed in related art patents. The relevant related art patents have in common an underground distribution system comprised of tubes through which the termiticide is dispensed into the surrounding underground area. Examples of these inventions are disclosed in the patents listed below:
What these patents fail to disclose or suggest is a structure or method of delivering termiticide that affects an effective delivery while minimizing the potentially adverse environmental impacts of delivering termiticide chemistry under a constructed building.
The prior art designs disclose xe2x80x9copen systemsxe2x80x9d that use high pressure underground termiticide delivery systems that are accessible from an above ground access port. In other words, the prior art underground delivery systems do not disclose a system capable of recapturing residual termiticides. Accordingly, any residual termiticide that remains in the deliver system after treatment may out gas through the above ground access port of the underground delivery system.
Further, the use of high pressure delivery methods affects an inefficient delivery of termiticide. Maintaining a constant elevated pressure throughout an underground piping system during delivery is difficult. ordinarily, high pressure underground delivery systems result in pressure gradients throughout the underground delivery system. The magnitude and dispersion of the pressure gradients in the system depends on many variables including the overall length of the delivery system, the diameter of the delivery piping, the radius of curvature of the delivery system piping corners, the distance of the delivery aperture from the pressure source, and the circumference of the delivery apertures. However, the adverse effect of each of these variables, and as a result the magnitudes of the pressure gradients, is augmented by the use of a relatively high-pressure delivery source. Accordingly, the effectiveness of termiticide delivery can be improved through a low-pressure delivery system.
Thus, there is a need for a pesticide deliver system that offers an improved and safer alternative to this dilemma in the form of an underground termiticide delivery system for periodic or xe2x80x9cas neededxe2x80x9d pesticide applications after construction of buildings. The present invention enables high-volume pesticide delivery to underneath a building structure while minimizing airborne or above ground pesticide dispersal and exposure to people as a result thereof. Accordingly, the present invention provides a more effective barrier to pests while minimizing the adverse consequences of relatively high-pressure underground pesticide delivery systems.
The present invention is a closed pesticide delivery system comprising a pesticide delivery apparatus and method of using the pesticide delivery apparatus. The pesticide delivery apparatus comprises a low-pressure pesticide propellant source, a propellant recovery reservoir, a prewetting and purging source, underground pesticide delivery tubing, and above ground hoses to connect the components of the apparatus. The method of using the present invention comprises the steps of: 1) prewetting with a water-based solutions of the underground adjacent to the underground pesticide delivery tubing; 2) propelling a pesticide solution through the underground pesticide delivery tubing and into the underground adjacent to the underground delivery tubing; and 3) purging, and verifying the purge, of the underground pesticide delivery tubing. Implementations of the invention are contemplated wherein the pesticide comprises a termiticide. Alternate implementations are also contemplated wherein the pesticide comprises biologically active nematodes either in place of or in combination with the termiticide.
The novel features that are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its structure and its operation together with the additional object and advantages thereof will best be understood from the following description of the preferred embodiment of the present invention when read in conjunction with the accompanying drawings. Unless specifically noted, it is intended that the words and phrases in the specification and claims be given the ordinary and accustomed meaning to those of ordinary skill in the applicable art or arts. If any other meaning is intended, the specification will specifically state that a special meaning is being applied to a word or phrase. Likewise, the use of the words xe2x80x9cfunctionxe2x80x9d or xe2x80x9cmeansxe2x80x9d in the Description of Preferred Embodiments is not intended to indicate a desire to invoke the special provision of 35 U.S.C. xc2xa7112, paragraph 6 to define the invention. To the contrary, if the provisions of 35 U.S.C. xc2xa7112, paragraph 6, are sought to be invoked to define the invention(s), the claims will specifically state the phrases xe2x80x9cmeans forxe2x80x9d or xe2x80x9cstep forxe2x80x9d and a function, without also reciting in such phrases any structure, material, or act in support of the function. Even when the claims recite a xe2x80x9cmeans forxe2x80x9d or xe2x80x9cstep forxe2x80x9d performing a function, if they also recite any structure, material or acts in support of that means of step, then the intention is not to invoke the provisions of 35 U.S.C. xc2xa7112, paragraph 6. Moreover, even if the provisions of 35 U.S.C. xc2xa7112, paragraph 6, are invoked to define the inventions, it is intended that the inventions not be limited only to the specific structure, material or acts that are described in the preferred embodiments, but in addition, include any and all structures, materials or acts that perform the claimed function, along with any and all known or later-developed equivalent structures, materials or acts for performing the claimed function.